Living Reviews in Solar Physics最新文献_第2页

Coronal bright points 日冕亮点

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2019-03-15 DOI: 10.1007/s41116-019-0018-8

Maria S. Madjarska

{"title":"Coronal bright points","authors":"Maria S. Madjarska","doi":"10.1007/s41116-019-0018-8","DOIUrl":"https://doi.org/10.1007/s41116-019-0018-8","url":null,"abstract":"Coronal bright points (CBPs) are a fundamental class of solar activity. They represent a set of low-corona small-scale loops with enhanced emission in the extreme-ultraviolet and X-ray spectrum that connect magnetic flux concentrations of opposite polarities. CBPs are one of the main building blocks of the solar atmosphere outside active regions uniformly populating the solar atmosphere including active region latitudes and coronal holes. Their plasma properties classify them as downscaled active regions. Most importantly, their simple structure and short lifetimes of less than 20?h that allow to follow their full lifetime evolution present a unique opportunity to investigate outstanding questions in solar physics including coronal heating. The present Living Review is the first review of this essential class of solar phenomena and aims to give an overview of the current knowledge about the CBP general, plasma and magnetic properties. Several transient dynamic phenomena associated with CBPs are also briefly introduced. The observationally derived energetics and the theoretical modelling that aims at explaining the CBP formation and eruptive behaviour are reviewed.","PeriodicalId":49147,"journal":{"name":"Living Reviews in Solar Physics","volume":null,"pages":null},"PeriodicalIF":20.9,"publicationDate":"2019-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41116-019-0018-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4619376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 41

Quiet Sun magnetic fields: an observational view 安静的太阳磁场:一个观测视图

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2019-02-18 DOI: 10.1007/s41116-018-0017-1

Luis Bellot Rubio, David Orozco Suárez

{"title":"Quiet Sun magnetic fields: an observational view","authors":"Luis Bellot Rubio, David Orozco Suárez","doi":"10.1007/s41116-018-0017-1","DOIUrl":"https://doi.org/10.1007/s41116-018-0017-1","url":null,"abstract":"The quiet Sun is the region of the solar surface outside of sunspots, pores, and plages. In continuum intensity it appears dominated by granular convection. However, in polarized light the quiet Sun exhibits impressive magnetic activity on a broad range of scales, from the 30,000?km of supergranular cells down to the smallest magnetic features of about 100?km resolvable with current instruments. Quiet Sun fields are observed to evolve in a coherent way, interacting with each other as they are advected by the horizontal photospheric flows. They appear and disappear over surprisingly short time scales, bringing large amounts of magnetic flux to the solar surface. For this reason they may be important contributors to the heating of the chromosphere. Peering into such fields is difficult because of the weak signals they produce, which are easily affected, and even completely hidden, by photon noise. Thus, their evolution and nature remain largely unknown. In recent years the situation has improved thanks to the advent of high-resolution, high-sensitivity spectropolarimetric measurements and the application of state-of-the-art Zeeman and Hanle effect diagnostics. Here we review this important aspect of solar magnetism, paying special attention to the techniques used to observe and characterize the fields, their evolution on the solar surface, and their physical properties as revealed by the most recent analyses. We identify the main open questions that need to be addressed in the future and offer some ideas on how to solve them.","PeriodicalId":49147,"journal":{"name":"Living Reviews in Solar Physics","volume":null,"pages":null},"PeriodicalIF":20.9,"publicationDate":"2019-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41116-018-0017-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4716113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 65

Solar UV and X-ray spectral diagnostics 太阳紫外线和x射线光谱诊断

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2018-08-31 DOI: 10.1007/s41116-018-0015-3

Giulio Del Zanna, Helen E. Mason

{"title":"Solar UV and X-ray spectral diagnostics","authors":"Giulio Del Zanna, Helen E. Mason","doi":"10.1007/s41116-018-0015-3","DOIUrl":"https://doi.org/10.1007/s41116-018-0015-3","url":null,"abstract":"X-ray and ultraviolet (UV) observations of the outer solar atmosphere have been used for many decades to measure the fundamental parameters of the solar plasma. This review focuses on the optically thin emission from the solar atmosphere, mostly found at UV and X-ray (XUV) wavelengths, and discusses some of the diagnostic methods that have been used to measure electron densities, electron temperatures, differential emission measure (DEM), and relative chemical abundances. We mainly focus on methods and results obtained from high-resolution spectroscopy, rather than broad-band imaging. However, we note that the best results are often obtained by combining imaging and spectroscopic observations. We also mainly focus the review on measurements of electron densities and temperatures obtained from single ion diagnostics, to avoid issues related to the ionisation state of the plasma. We start the review with a short historical introduction on the main XUV high-resolution spectrometers, then review the basics of optically thin emission and the main processes that affect the formation of a spectral line. We mainly discuss plasma in equilibrium, but briefly mention non-equilibrium ionisation and non-thermal electron distributions. We also summarise the status of atomic data, which are an essential part of the diagnostic process. We then review the methods used to measure electron densities, electron temperatures, the DEM, and relative chemical abundances, and the results obtained for the lower solar atmosphere (within a fraction of the solar radii), for coronal holes, the quiet Sun, active regions and flares.","PeriodicalId":49147,"journal":{"name":"Living Reviews in Solar Physics","volume":null,"pages":null},"PeriodicalIF":20.9,"publicationDate":"2018-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41116-018-0015-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5171758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 128

Extended MHD modeling of the steady solar corona and the solar wind 稳定日冕和太阳风的扩展MHD模型

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2018-07-30 DOI: 10.1007/s41116-018-0014-4

Tamas I. Gombosi, Bart van der Holst, Ward B. Manchester, Igor V. Sokolov

引用次数: 67

Prominence oscillations 突出振荡

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2018-04-23 DOI: 10.1007/s41116-018-0012-6

Iñigo Arregui, Ramón Oliver, José Luis Ballester

引用次数: 12

Solar wind stream interaction regions throughout the heliosphere 整个日球层的太阳风流相互作用区域

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2018-01-26 DOI: 10.1007/s41116-017-0011-z

Ian G. Richardson

引用次数: 178

Inversion of the radiative transfer equation for polarized light 偏振光辐射传递方程的反演

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2016-11-23 DOI: 10.1007/s41116-016-0005-2

Jose Carlos del Toro Iniesta, Basilio Ruiz Cobo

{"title":"Inversion of the radiative transfer equation for polarized light","authors":"Jose Carlos del Toro Iniesta, Basilio Ruiz Cobo","doi":"10.1007/s41116-016-0005-2","DOIUrl":"https://doi.org/10.1007/s41116-016-0005-2","url":null,"abstract":"Since the early 1970s, inversion techniques have become the most useful tool for inferring the magnetic, dynamic, and thermodynamic properties of the solar atmosphere. Inversions have been proposed in the literature with a sequential increase in model complexity: astrophysical inferences depend not only on measurements but also on the physics assumed to prevail both on the formation of the spectral line Stokes profiles and on their detection with the instrument. Such an intrinsic model dependence makes it necessary to formulate specific means that include the physics in a properly quantitative way. The core of this physics lies in the radiative transfer equation (RTE), where the properties of the atmosphere are assumed to be known while the unknowns are the four Stokes profiles. The solution of the (differential) RTE is known as the direct or forward problem. From an observational point of view, the problem is rather the opposite: the data are made up of the observed Stokes profiles and the unknowns are the solar physical quantities. Inverting the RTE is therefore mandatory. Indeed, the formal solution of this equation can be considered an integral equation. The solution of such an integral equation is called the inverse problem. Inversion techniques are automated codes aimed at solving the inverse problem. The foundations of inversion techniques are critically revisited with an emphasis on making explicit the many assumptions underlying each of them.","PeriodicalId":49147,"journal":{"name":"Living Reviews in Solar Physics","volume":null,"pages":null},"PeriodicalIF":20.9,"publicationDate":"2016-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41116-016-0005-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4912317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 78

Large gradual solar energetic particle events 大型的渐进式太阳高能粒子事件

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2016-09-07 DOI: 10.1007/s41116-016-0002-5

Mihir Desai, Joe Giacalone

{"title":"Large gradual solar energetic particle events","authors":"Mihir Desai, Joe Giacalone","doi":"10.1007/s41116-016-0002-5","DOIUrl":"https://doi.org/10.1007/s41116-016-0002-5","url":null,"abstract":"Solar energetic particles, or SEPs, from suprathermal (few keV) up to relativistic ((sim )few GeV) energies are accelerated near the Sun in at least two ways: (1) by magnetic reconnection-driven processes during solar flares resulting in impulsive SEPs, and (2) at fast coronal-mass-ejection-driven shock waves that produce large gradual SEP events. Large gradual SEP events are of particular interest because the accompanying high-energy (({>}10)s?MeV) protons pose serious radiation threats to human explorers living and working beyond low-Earth orbit and to technological assets such as communications and scientific satellites in space. However, a complete understanding of these large SEP events has eluded us primarily because their properties, as observed in Earth orbit, are smeared due to mixing and contributions from many important physical effects. This paper provides a comprehensive review of the current state of knowledge of these important phenomena, and summarizes some of the key questions that will be addressed by two upcoming missions—NASA’s Solar Probe Plus and ESA’s Solar Orbiter. Both of these missions are designed to directly and repeatedly sample the near-Sun environments where interplanetary scattering and transport effects are significantly reduced, allowing us to discriminate between different acceleration sites and mechanisms and to isolate the contributions of numerous physical processes occurring during large SEP events.","PeriodicalId":49147,"journal":{"name":"Living Reviews in Solar Physics","volume":null,"pages":null},"PeriodicalIF":20.9,"publicationDate":"2016-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/s41116-016-0002-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"4323252","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 306

Global seismology of the Sun 全球太阳地震学

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2016-08-08 DOI: 10.1007/s41116-016-0003-4

Sarbani Basu

引用次数: 79

Solar and stellar photospheric abundances 太阳和恒星的光球丰度

IF 20.9 1区物理与天体物理

Living Reviews in Solar Physics Pub Date : 2016-07-05 DOI: 10.1007/s41116-016-0001-6

Carlos Allende Prieto

引用次数: 15